Small marine pleasure craft may take a variety of forms, from conventional boats to hibred vehicles. currently popular craft is the jet ski, an exemplary depiction of which may be found in U.S. Pat. No. 4,628,852, granted Dec. 16, 1986, to Nishida et al.
In the operation of a jet ski at cruising speeds, the craft has a strong tendency to pitch fore and aft in a motion which has come to be called "porpoising" because of a high degree of similarity in appearance to the motion of a porpoise as it moves along the surface of a body of water. This porpoising or pitching motion is very distracting and disconcerting to the operator or occupant of the craft, contributes significantly to operator fatigue, and detracts from the enjoyment and exhilaration of the sport of jet skiing.
Another problematic tendency of many jet skis is to slide or skid sideways or laterally across the water when an attempt is made to turn at cruising speeds, thereby detracting from the maneuverability and safety of operation of the craft.